Cell phones, PDAs and other portable electronic devices are extremely prevalent. People are increasingly relying upon these devices for a range of purposes. For example, while cell phones were originally most commonly used by business travelers, they are now more widely used. For example, teens may carry cell phones in order to communicate with their parents in the event of an emergency, to communicate with their friends at school, or at home without tying up a home phone land line. In some cases, people are using their cell phone in replacement of their land lines. Similarly, PDAs have grown in popularity, owing to the range of functions they now provide.
One problem with these devices is, being portable, they are powered by a battery that requires frequent charging. Often, a user may find that their cell phone is not fully charged, and they may lose power during use. Loss of battery power to a PDA or cell phone can even result in loss of stored information.
Generally, these devices are charged by connecting them to a power source via a charging cable. Most commonly, these devices are provided with a “home” charging cable which allows the device to be charged via a 110V AC power source, such as the type commonly found in the home at a wall outlet. The device may also be provided with a “car” charger which allows the device to be charged via a 12V DC power source, such as the type commonly found in an automobile.
However, the device owner may forget their charger. For example, a traveler may forget to bring their home or car charger with them and arrive at a remote destination with no way to charge their device. Similarly, even if one charges their cell phone or PDA at home during the evening, the battery power may be depleted the next day when the device is used at school, at work or at another remote location. The user may then not be able to charge the device until they return home that evening.
One solution to this problem is to obtain an additional or backup battery. This battery may be charged at the same time as the main device battery and be transported with the device. If the main battery loses its charge, the second battery may be placed in the device. This, however, is a cumbersome solution to the problem. The solution requires one to purchase an expensive battery and keep that battery, like the battery in the main device, charged up. If one travels for a few days, the charge in both batteries may quickly be depleted, leaving the user without use of their device once again.